linux/drivers/base/cacheinfo.c
Linus Torvalds f632a8170a Driver Core and debugfs changes for 5.3-rc1
Here is the "big" driver core and debugfs changes for 5.3-rc1
 
 It's a lot of different patches, all across the tree due to some api
 changes and lots of debugfs cleanups.  Because of this, there is going
 to be some merge issues with your tree at the moment, I'll follow up
 with the expected resolutions to make it easier for you.
 
 Other than the debugfs cleanups, in this set of changes we have:
 	- bus iteration function cleanups (will cause build warnings
 	  with s390 and coresight drivers in your tree)
 	- scripts/get_abi.pl tool to display and parse Documentation/ABI
 	  entries in a simple way
 	- cleanups to Documenatation/ABI/ entries to make them parse
 	  easier due to typos and other minor things
 	- default_attrs use for some ktype users
 	- driver model documentation file conversions to .rst
 	- compressed firmware file loading
 	- deferred probe fixes
 
 All of these have been in linux-next for a while, with a bunch of merge
 issues that Stephen has been patient with me for.  Other than the merge
 issues, functionality is working properly in linux-next :)
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core and debugfs updates from Greg KH:
 "Here is the "big" driver core and debugfs changes for 5.3-rc1

  It's a lot of different patches, all across the tree due to some api
  changes and lots of debugfs cleanups.

  Other than the debugfs cleanups, in this set of changes we have:

   - bus iteration function cleanups

   - scripts/get_abi.pl tool to display and parse Documentation/ABI
     entries in a simple way

   - cleanups to Documenatation/ABI/ entries to make them parse easier
     due to typos and other minor things

   - default_attrs use for some ktype users

   - driver model documentation file conversions to .rst

   - compressed firmware file loading

   - deferred probe fixes

  All of these have been in linux-next for a while, with a bunch of
  merge issues that Stephen has been patient with me for"

* tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits)
  debugfs: make error message a bit more verbose
  orangefs: fix build warning from debugfs cleanup patch
  ubifs: fix build warning after debugfs cleanup patch
  driver: core: Allow subsystems to continue deferring probe
  drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT
  arch_topology: Remove error messages on out-of-memory conditions
  lib: notifier-error-inject: no need to check return value of debugfs_create functions
  swiotlb: no need to check return value of debugfs_create functions
  ceph: no need to check return value of debugfs_create functions
  sunrpc: no need to check return value of debugfs_create functions
  ubifs: no need to check return value of debugfs_create functions
  orangefs: no need to check return value of debugfs_create functions
  nfsd: no need to check return value of debugfs_create functions
  lib: 842: no need to check return value of debugfs_create functions
  debugfs: provide pr_fmt() macro
  debugfs: log errors when something goes wrong
  drivers: s390/cio: Fix compilation warning about const qualifiers
  drivers: Add generic helper to match by of_node
  driver_find_device: Unify the match function with class_find_device()
  bus_find_device: Unify the match callback with class_find_device
  ...
2019-07-12 12:24:03 -07:00

668 lines
17 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* cacheinfo support - processor cache information via sysfs
*
* Based on arch/x86/kernel/cpu/intel_cacheinfo.c
* Author: Sudeep Holla <sudeep.holla@arm.com>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/acpi.h>
#include <linux/bitops.h>
#include <linux/cacheinfo.h>
#include <linux/compiler.h>
#include <linux/cpu.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/smp.h>
#include <linux/sysfs.h>
/* pointer to per cpu cacheinfo */
static DEFINE_PER_CPU(struct cpu_cacheinfo, ci_cpu_cacheinfo);
#define ci_cacheinfo(cpu) (&per_cpu(ci_cpu_cacheinfo, cpu))
#define cache_leaves(cpu) (ci_cacheinfo(cpu)->num_leaves)
#define per_cpu_cacheinfo(cpu) (ci_cacheinfo(cpu)->info_list)
struct cpu_cacheinfo *get_cpu_cacheinfo(unsigned int cpu)
{
return ci_cacheinfo(cpu);
}
#ifdef CONFIG_OF
static inline bool cache_leaves_are_shared(struct cacheinfo *this_leaf,
struct cacheinfo *sib_leaf)
{
return sib_leaf->fw_token == this_leaf->fw_token;
}
/* OF properties to query for a given cache type */
struct cache_type_info {
const char *size_prop;
const char *line_size_props[2];
const char *nr_sets_prop;
};
static const struct cache_type_info cache_type_info[] = {
{
.size_prop = "cache-size",
.line_size_props = { "cache-line-size",
"cache-block-size", },
.nr_sets_prop = "cache-sets",
}, {
.size_prop = "i-cache-size",
.line_size_props = { "i-cache-line-size",
"i-cache-block-size", },
.nr_sets_prop = "i-cache-sets",
}, {
.size_prop = "d-cache-size",
.line_size_props = { "d-cache-line-size",
"d-cache-block-size", },
.nr_sets_prop = "d-cache-sets",
},
};
static inline int get_cacheinfo_idx(enum cache_type type)
{
if (type == CACHE_TYPE_UNIFIED)
return 0;
return type;
}
static void cache_size(struct cacheinfo *this_leaf, struct device_node *np)
{
const char *propname;
int ct_idx;
ct_idx = get_cacheinfo_idx(this_leaf->type);
propname = cache_type_info[ct_idx].size_prop;
of_property_read_u32(np, propname, &this_leaf->size);
}
/* not cache_line_size() because that's a macro in include/linux/cache.h */
static void cache_get_line_size(struct cacheinfo *this_leaf,
struct device_node *np)
{
int i, lim, ct_idx;
ct_idx = get_cacheinfo_idx(this_leaf->type);
lim = ARRAY_SIZE(cache_type_info[ct_idx].line_size_props);
for (i = 0; i < lim; i++) {
int ret;
u32 line_size;
const char *propname;
propname = cache_type_info[ct_idx].line_size_props[i];
ret = of_property_read_u32(np, propname, &line_size);
if (!ret) {
this_leaf->coherency_line_size = line_size;
break;
}
}
}
static void cache_nr_sets(struct cacheinfo *this_leaf, struct device_node *np)
{
const char *propname;
int ct_idx;
ct_idx = get_cacheinfo_idx(this_leaf->type);
propname = cache_type_info[ct_idx].nr_sets_prop;
of_property_read_u32(np, propname, &this_leaf->number_of_sets);
}
static void cache_associativity(struct cacheinfo *this_leaf)
{
unsigned int line_size = this_leaf->coherency_line_size;
unsigned int nr_sets = this_leaf->number_of_sets;
unsigned int size = this_leaf->size;
/*
* If the cache is fully associative, there is no need to
* check the other properties.
*/
if (!(nr_sets == 1) && (nr_sets > 0 && size > 0 && line_size > 0))
this_leaf->ways_of_associativity = (size / nr_sets) / line_size;
}
static bool cache_node_is_unified(struct cacheinfo *this_leaf,
struct device_node *np)
{
return of_property_read_bool(np, "cache-unified");
}
static void cache_of_set_props(struct cacheinfo *this_leaf,
struct device_node *np)
{
/*
* init_cache_level must setup the cache level correctly
* overriding the architecturally specified levels, so
* if type is NONE at this stage, it should be unified
*/
if (this_leaf->type == CACHE_TYPE_NOCACHE &&
cache_node_is_unified(this_leaf, np))
this_leaf->type = CACHE_TYPE_UNIFIED;
cache_size(this_leaf, np);
cache_get_line_size(this_leaf, np);
cache_nr_sets(this_leaf, np);
cache_associativity(this_leaf);
}
static int cache_setup_of_node(unsigned int cpu)
{
struct device_node *np;
struct cacheinfo *this_leaf;
struct device *cpu_dev = get_cpu_device(cpu);
struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
unsigned int index = 0;
/* skip if fw_token is already populated */
if (this_cpu_ci->info_list->fw_token) {
return 0;
}
if (!cpu_dev) {
pr_err("No cpu device for CPU %d\n", cpu);
return -ENODEV;
}
np = cpu_dev->of_node;
if (!np) {
pr_err("Failed to find cpu%d device node\n", cpu);
return -ENOENT;
}
while (index < cache_leaves(cpu)) {
this_leaf = this_cpu_ci->info_list + index;
if (this_leaf->level != 1)
np = of_find_next_cache_node(np);
else
np = of_node_get(np);/* cpu node itself */
if (!np)
break;
cache_of_set_props(this_leaf, np);
this_leaf->fw_token = np;
index++;
}
if (index != cache_leaves(cpu)) /* not all OF nodes populated */
return -ENOENT;
return 0;
}
#else
static inline int cache_setup_of_node(unsigned int cpu) { return 0; }
static inline bool cache_leaves_are_shared(struct cacheinfo *this_leaf,
struct cacheinfo *sib_leaf)
{
/*
* For non-DT/ACPI systems, assume unique level 1 caches, system-wide
* shared caches for all other levels. This will be used only if
* arch specific code has not populated shared_cpu_map
*/
return !(this_leaf->level == 1);
}
#endif
int __weak cache_setup_acpi(unsigned int cpu)
{
return -ENOTSUPP;
}
unsigned int coherency_max_size;
static int cache_shared_cpu_map_setup(unsigned int cpu)
{
struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
struct cacheinfo *this_leaf, *sib_leaf;
unsigned int index;
int ret = 0;
if (this_cpu_ci->cpu_map_populated)
return 0;
if (of_have_populated_dt())
ret = cache_setup_of_node(cpu);
else if (!acpi_disabled)
ret = cache_setup_acpi(cpu);
if (ret)
return ret;
for (index = 0; index < cache_leaves(cpu); index++) {
unsigned int i;
this_leaf = this_cpu_ci->info_list + index;
/* skip if shared_cpu_map is already populated */
if (!cpumask_empty(&this_leaf->shared_cpu_map))
continue;
cpumask_set_cpu(cpu, &this_leaf->shared_cpu_map);
for_each_online_cpu(i) {
struct cpu_cacheinfo *sib_cpu_ci = get_cpu_cacheinfo(i);
if (i == cpu || !sib_cpu_ci->info_list)
continue;/* skip if itself or no cacheinfo */
sib_leaf = sib_cpu_ci->info_list + index;
if (cache_leaves_are_shared(this_leaf, sib_leaf)) {
cpumask_set_cpu(cpu, &sib_leaf->shared_cpu_map);
cpumask_set_cpu(i, &this_leaf->shared_cpu_map);
}
}
/* record the maximum cache line size */
if (this_leaf->coherency_line_size > coherency_max_size)
coherency_max_size = this_leaf->coherency_line_size;
}
return 0;
}
static void cache_shared_cpu_map_remove(unsigned int cpu)
{
struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
struct cacheinfo *this_leaf, *sib_leaf;
unsigned int sibling, index;
for (index = 0; index < cache_leaves(cpu); index++) {
this_leaf = this_cpu_ci->info_list + index;
for_each_cpu(sibling, &this_leaf->shared_cpu_map) {
struct cpu_cacheinfo *sib_cpu_ci;
if (sibling == cpu) /* skip itself */
continue;
sib_cpu_ci = get_cpu_cacheinfo(sibling);
if (!sib_cpu_ci->info_list)
continue;
sib_leaf = sib_cpu_ci->info_list + index;
cpumask_clear_cpu(cpu, &sib_leaf->shared_cpu_map);
cpumask_clear_cpu(sibling, &this_leaf->shared_cpu_map);
}
if (of_have_populated_dt())
of_node_put(this_leaf->fw_token);
}
}
static void free_cache_attributes(unsigned int cpu)
{
if (!per_cpu_cacheinfo(cpu))
return;
cache_shared_cpu_map_remove(cpu);
kfree(per_cpu_cacheinfo(cpu));
per_cpu_cacheinfo(cpu) = NULL;
}
int __weak init_cache_level(unsigned int cpu)
{
return -ENOENT;
}
int __weak populate_cache_leaves(unsigned int cpu)
{
return -ENOENT;
}
static int detect_cache_attributes(unsigned int cpu)
{
int ret;
if (init_cache_level(cpu) || !cache_leaves(cpu))
return -ENOENT;
per_cpu_cacheinfo(cpu) = kcalloc(cache_leaves(cpu),
sizeof(struct cacheinfo), GFP_KERNEL);
if (per_cpu_cacheinfo(cpu) == NULL)
return -ENOMEM;
/*
* populate_cache_leaves() may completely setup the cache leaves and
* shared_cpu_map or it may leave it partially setup.
*/
ret = populate_cache_leaves(cpu);
if (ret)
goto free_ci;
/*
* For systems using DT for cache hierarchy, fw_token
* and shared_cpu_map will be set up here only if they are
* not populated already
*/
ret = cache_shared_cpu_map_setup(cpu);
if (ret) {
pr_warn("Unable to detect cache hierarchy for CPU %d\n", cpu);
goto free_ci;
}
return 0;
free_ci:
free_cache_attributes(cpu);
return ret;
}
/* pointer to cpuX/cache device */
static DEFINE_PER_CPU(struct device *, ci_cache_dev);
#define per_cpu_cache_dev(cpu) (per_cpu(ci_cache_dev, cpu))
static cpumask_t cache_dev_map;
/* pointer to array of devices for cpuX/cache/indexY */
static DEFINE_PER_CPU(struct device **, ci_index_dev);
#define per_cpu_index_dev(cpu) (per_cpu(ci_index_dev, cpu))
#define per_cache_index_dev(cpu, idx) ((per_cpu_index_dev(cpu))[idx])
#define show_one(file_name, object) \
static ssize_t file_name##_show(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct cacheinfo *this_leaf = dev_get_drvdata(dev); \
return sprintf(buf, "%u\n", this_leaf->object); \
}
show_one(id, id);
show_one(level, level);
show_one(coherency_line_size, coherency_line_size);
show_one(number_of_sets, number_of_sets);
show_one(physical_line_partition, physical_line_partition);
show_one(ways_of_associativity, ways_of_associativity);
static ssize_t size_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct cacheinfo *this_leaf = dev_get_drvdata(dev);
return sprintf(buf, "%uK\n", this_leaf->size >> 10);
}
static ssize_t shared_cpumap_show_func(struct device *dev, bool list, char *buf)
{
struct cacheinfo *this_leaf = dev_get_drvdata(dev);
const struct cpumask *mask = &this_leaf->shared_cpu_map;
return cpumap_print_to_pagebuf(list, buf, mask);
}
static ssize_t shared_cpu_map_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return shared_cpumap_show_func(dev, false, buf);
}
static ssize_t shared_cpu_list_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return shared_cpumap_show_func(dev, true, buf);
}
static ssize_t type_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct cacheinfo *this_leaf = dev_get_drvdata(dev);
switch (this_leaf->type) {
case CACHE_TYPE_DATA:
return sprintf(buf, "Data\n");
case CACHE_TYPE_INST:
return sprintf(buf, "Instruction\n");
case CACHE_TYPE_UNIFIED:
return sprintf(buf, "Unified\n");
default:
return -EINVAL;
}
}
static ssize_t allocation_policy_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct cacheinfo *this_leaf = dev_get_drvdata(dev);
unsigned int ci_attr = this_leaf->attributes;
int n = 0;
if ((ci_attr & CACHE_READ_ALLOCATE) && (ci_attr & CACHE_WRITE_ALLOCATE))
n = sprintf(buf, "ReadWriteAllocate\n");
else if (ci_attr & CACHE_READ_ALLOCATE)
n = sprintf(buf, "ReadAllocate\n");
else if (ci_attr & CACHE_WRITE_ALLOCATE)
n = sprintf(buf, "WriteAllocate\n");
return n;
}
static ssize_t write_policy_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct cacheinfo *this_leaf = dev_get_drvdata(dev);
unsigned int ci_attr = this_leaf->attributes;
int n = 0;
if (ci_attr & CACHE_WRITE_THROUGH)
n = sprintf(buf, "WriteThrough\n");
else if (ci_attr & CACHE_WRITE_BACK)
n = sprintf(buf, "WriteBack\n");
return n;
}
static DEVICE_ATTR_RO(id);
static DEVICE_ATTR_RO(level);
static DEVICE_ATTR_RO(type);
static DEVICE_ATTR_RO(coherency_line_size);
static DEVICE_ATTR_RO(ways_of_associativity);
static DEVICE_ATTR_RO(number_of_sets);
static DEVICE_ATTR_RO(size);
static DEVICE_ATTR_RO(allocation_policy);
static DEVICE_ATTR_RO(write_policy);
static DEVICE_ATTR_RO(shared_cpu_map);
static DEVICE_ATTR_RO(shared_cpu_list);
static DEVICE_ATTR_RO(physical_line_partition);
static struct attribute *cache_default_attrs[] = {
&dev_attr_id.attr,
&dev_attr_type.attr,
&dev_attr_level.attr,
&dev_attr_shared_cpu_map.attr,
&dev_attr_shared_cpu_list.attr,
&dev_attr_coherency_line_size.attr,
&dev_attr_ways_of_associativity.attr,
&dev_attr_number_of_sets.attr,
&dev_attr_size.attr,
&dev_attr_allocation_policy.attr,
&dev_attr_write_policy.attr,
&dev_attr_physical_line_partition.attr,
NULL
};
static umode_t
cache_default_attrs_is_visible(struct kobject *kobj,
struct attribute *attr, int unused)
{
struct device *dev = kobj_to_dev(kobj);
struct cacheinfo *this_leaf = dev_get_drvdata(dev);
const struct cpumask *mask = &this_leaf->shared_cpu_map;
umode_t mode = attr->mode;
if ((attr == &dev_attr_id.attr) && (this_leaf->attributes & CACHE_ID))
return mode;
if ((attr == &dev_attr_type.attr) && this_leaf->type)
return mode;
if ((attr == &dev_attr_level.attr) && this_leaf->level)
return mode;
if ((attr == &dev_attr_shared_cpu_map.attr) && !cpumask_empty(mask))
return mode;
if ((attr == &dev_attr_shared_cpu_list.attr) && !cpumask_empty(mask))
return mode;
if ((attr == &dev_attr_coherency_line_size.attr) &&
this_leaf->coherency_line_size)
return mode;
if ((attr == &dev_attr_ways_of_associativity.attr) &&
this_leaf->size) /* allow 0 = full associativity */
return mode;
if ((attr == &dev_attr_number_of_sets.attr) &&
this_leaf->number_of_sets)
return mode;
if ((attr == &dev_attr_size.attr) && this_leaf->size)
return mode;
if ((attr == &dev_attr_write_policy.attr) &&
(this_leaf->attributes & CACHE_WRITE_POLICY_MASK))
return mode;
if ((attr == &dev_attr_allocation_policy.attr) &&
(this_leaf->attributes & CACHE_ALLOCATE_POLICY_MASK))
return mode;
if ((attr == &dev_attr_physical_line_partition.attr) &&
this_leaf->physical_line_partition)
return mode;
return 0;
}
static const struct attribute_group cache_default_group = {
.attrs = cache_default_attrs,
.is_visible = cache_default_attrs_is_visible,
};
static const struct attribute_group *cache_default_groups[] = {
&cache_default_group,
NULL,
};
static const struct attribute_group *cache_private_groups[] = {
&cache_default_group,
NULL, /* Place holder for private group */
NULL,
};
const struct attribute_group *
__weak cache_get_priv_group(struct cacheinfo *this_leaf)
{
return NULL;
}
static const struct attribute_group **
cache_get_attribute_groups(struct cacheinfo *this_leaf)
{
const struct attribute_group *priv_group =
cache_get_priv_group(this_leaf);
if (!priv_group)
return cache_default_groups;
if (!cache_private_groups[1])
cache_private_groups[1] = priv_group;
return cache_private_groups;
}
/* Add/Remove cache interface for CPU device */
static void cpu_cache_sysfs_exit(unsigned int cpu)
{
int i;
struct device *ci_dev;
if (per_cpu_index_dev(cpu)) {
for (i = 0; i < cache_leaves(cpu); i++) {
ci_dev = per_cache_index_dev(cpu, i);
if (!ci_dev)
continue;
device_unregister(ci_dev);
}
kfree(per_cpu_index_dev(cpu));
per_cpu_index_dev(cpu) = NULL;
}
device_unregister(per_cpu_cache_dev(cpu));
per_cpu_cache_dev(cpu) = NULL;
}
static int cpu_cache_sysfs_init(unsigned int cpu)
{
struct device *dev = get_cpu_device(cpu);
if (per_cpu_cacheinfo(cpu) == NULL)
return -ENOENT;
per_cpu_cache_dev(cpu) = cpu_device_create(dev, NULL, NULL, "cache");
if (IS_ERR(per_cpu_cache_dev(cpu)))
return PTR_ERR(per_cpu_cache_dev(cpu));
/* Allocate all required memory */
per_cpu_index_dev(cpu) = kcalloc(cache_leaves(cpu),
sizeof(struct device *), GFP_KERNEL);
if (unlikely(per_cpu_index_dev(cpu) == NULL))
goto err_out;
return 0;
err_out:
cpu_cache_sysfs_exit(cpu);
return -ENOMEM;
}
static int cache_add_dev(unsigned int cpu)
{
unsigned int i;
int rc;
struct device *ci_dev, *parent;
struct cacheinfo *this_leaf;
struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
const struct attribute_group **cache_groups;
rc = cpu_cache_sysfs_init(cpu);
if (unlikely(rc < 0))
return rc;
parent = per_cpu_cache_dev(cpu);
for (i = 0; i < cache_leaves(cpu); i++) {
this_leaf = this_cpu_ci->info_list + i;
if (this_leaf->disable_sysfs)
continue;
if (this_leaf->type == CACHE_TYPE_NOCACHE)
break;
cache_groups = cache_get_attribute_groups(this_leaf);
ci_dev = cpu_device_create(parent, this_leaf, cache_groups,
"index%1u", i);
if (IS_ERR(ci_dev)) {
rc = PTR_ERR(ci_dev);
goto err;
}
per_cache_index_dev(cpu, i) = ci_dev;
}
cpumask_set_cpu(cpu, &cache_dev_map);
return 0;
err:
cpu_cache_sysfs_exit(cpu);
return rc;
}
static int cacheinfo_cpu_online(unsigned int cpu)
{
int rc = detect_cache_attributes(cpu);
if (rc)
return rc;
rc = cache_add_dev(cpu);
if (rc)
free_cache_attributes(cpu);
return rc;
}
static int cacheinfo_cpu_pre_down(unsigned int cpu)
{
if (cpumask_test_and_clear_cpu(cpu, &cache_dev_map))
cpu_cache_sysfs_exit(cpu);
free_cache_attributes(cpu);
return 0;
}
static int __init cacheinfo_sysfs_init(void)
{
return cpuhp_setup_state(CPUHP_AP_BASE_CACHEINFO_ONLINE,
"base/cacheinfo:online",
cacheinfo_cpu_online, cacheinfo_cpu_pre_down);
}
device_initcall(cacheinfo_sysfs_init);